In wireless communication systems, the process of scheduling users for communication plays an important role for the overall performance. Scheduling is normally part of the general resource management, and typically involves allocating communication resources, such as the transmission resources of a shared radio medium, to users according to some priority order.
Scheduling is of outmost importance in many wireless applications and system environments such as the IP Multimedia Subsystem (IMS) that supports user-to-user communication services. For example, real-time user-to-user multimedia telephony (MMTel) services play a key role to satisfy the needs of different services and to improve perceptual quality. In particular, when a lot of users enjoy the services, the available communication resources need to be allocated efficiently. This requires an efficient strategy and implementation for scheduling user access to the communication resources.
In modern communication systems such as packet based wireless systems, like High Speed Packet Access (HSPA) systems with Enhanced. Uplink (EUL), or Long Term Evolution (LTE) systems, the scheduler is a key element to provide higher data rates, reduced latency and improved system capacity.
There is thus a general demand for efficient scheduling in wireless communications.